Terra-cotta-firing system



TERRA GOTTA FIRING SYSTEM Filed April 15. 1927' 2 Sheets-Sheet 1 IN V EN TOR.

Alberg H- ShaHield A. H. SHEFFIELD Q 1,749,988

March 11, .1930; A. H. SHEFFIELD IERRA GOTTA FIRING SYSTEM Filed April 15. 1927 Sheets-Sheet 2 -fima i i i ld Patented Mar. 11 1930 PATENT OFFICE ALBERT E. SHEFFIELD, on Kansas crrY, Kansas TERRA-GOTTA-FIBING SYSTEM Application filed April 15,

This invention relates to the firing of terra cotta kilns, and has for its primary object, the provision of a novelly constructed system for the firing of open kilns of any size or capacity;

Heretofore, it is well known, that kilns used in the firing of terracotta have been essen tially equipped with a muffle, which required replacement, which'was expensive to keep up,

and which oftentimes was leaky, resulting in the ruining of a kiln of ware, and which re quired additional fuel to heat the same, and additional time in cooling after the ware had been burned.

Accordingly, one of the principal objects ofthe instant invention is to provide a sim: ply constructed kiln, which is comparatively inexpensive, much more efiicient to operate, and which performs the required duty even better than the old ordinary kilniheretofore used. r

1 An even further object of this invention is the'provision of a kiln for the firing of terra cotta which does not include the well known fire brick muflie, and which may be operated at a decided saving with respect to the time and labor required. p

Another object of this invention is the provision of a new combination of gas burning appliances, which are novelly arranged to cooperate with the new type of kiln insuch a manner that the entire burning system is extremely desirable, easy to operate, not likely to get out of order, and performs a more thoro piece of work at a decided saving.

Minorobjects of this invention will appear during the course of the detailed specification referring to the accompanying drawings, wherein Figure 1, is a side elevation of a terra cotta firing kiln, and system made in accordance with this invention.

Fig. 2, is a horizontal cross-section of the same, taken on line II-II of Fig. 1.

Fig. 3, is a vertical central section taken thru the kiln on line III-III of Fig. 2.

Fig. 4, is an enlarged longitudinal central section, taken thru the restricted throat and mixing chamber.

Fig. 5, is a fragmentagy sectional view 1927. Serial No. 183,948.

showingthe window tube, thru which the ware may be observed, and

"Fig. 6, is a vertical central section thru a modified form of kiln construction.

.Similar reference characters refer to like parts thruoutthe several views, and the numeral 7 designates the side walls of the round type, which when constructed in accordance with this invention, has atop 8, which terminates in a central stack 9, and which has a bag wall 10 extending around theinner chamber, and spaced apart from wall 7 by any suitable spacing element 12, to form an annu larjchamber which is in communication with a plurality of openings 13, extending thru wall 7. i i r r r It is notable that this kiln construction does not include a muffle wallwhich will burn out often, and cause other troubles well known in the art. A heat measuring device as.

14, of any suitable character may be used in connection with'the kiln, and the ware to be burned may be stacked in the well known fashionto completely fill the kiln prior to. firing. In firing terra cotta with a system contemplated by this invention, the products of combustion are allowed to come in direct contact with the ware, and the system shown utilizes gas for a fuel. In constructing a kiln, an air line 15 should lead from any suitable compressor and-surround the kiln ata point above openings 18; A single gas main p 16 may be used to supplyall of theburners,

andzsince each burner is feeding. a flame in the kilnthru an opening 13', butone will be herefully described. The" gas flowing from main 16 thru the lead-in 17 enters governor 18,.where it is reduced to zero pressure. From this point the gas is pulled inby the 0 energy furnished by the pressure of the air which enters the throat 19 from a conduit 20, leading from. the main air line 15. The amount of air passing thru the conduit20 tothroat 119 may be controlled by any suitable aircock 21, and as itpasses thru the restricted throat 22, the gas whichflows from governor 18, thru pipe 23is drawn in thru perforations 2 l at a point where. the air passin thru, the restricted throat reaches vem0 locity read immedia e y. s i 1 11 913 1 39 tomatically converted to a pressure head, suitable for delivery to the burners thru pipe connection 27; The amount. of. gas-allowed to enter my be controlledby a valve not here shown, and the mixture is ignited at the burner nozzle 28,positioned inside of the openin 13. Combustiontakes-place at the end of burner nozzle 28, and the fire is diverted upwardly by bag wall 10, which should terminate at a height equal to approximately one third the height of the kiln. As shown in Figure 2, this bag wall. extends: completely around the kiln, and the: equal distribution of the plurality of burners; around the kiln insures even temperature- In the formshown in. Fig. 6-,. the construction illustrated is desirable only when large kilns are being constructed, and it is desired to convey some of the heat; to the center where some of the heat from the burners maypass thru tunnels 29 to the center of tliefioor, which will help mature the warein the center of the kiln. Also, in largekilns, an additional inner stack 30 is constructed, leading to the central stack 9. The bottom of stack 30 may have a large number-of openings 31,.thru which the flue es will escape after having risen over the Eigwallto the crown ofthe kiln, and thence down to the floor again.-

. It isaplain to be seen, that this method of open firing is a departure fromthe established practice, and since; the time of burningis cut in half, and. since therate of cooling iamore; rapid, the system is extremely desira'ble; It has been found that the ware burned in these kilns does. not crack, and it is.

obvious that the removal of mufile walls, addifional stacks: and the like, will greatly in-.

crease the .eapacityof every kiln. It is also notable thatkilns now in use may be supplied with systems of this character;- Heretofore,

the use of coal or like fuel has caused the re,--

has determined the fact that carbon in the clay is oxidized at about 1350 degrees F. and up to this point the operator should be careful not to close the damper too much. After the kiln has reached this point, it has been found that the same may be run under pressure if desired.

Manifestly, the novel points of this system are extremely important, and valuable in the art. It is understood that various modifications may be made without departing from the spirit of the invention, and having thus described the preferred embodiment of a terra cottav burning system, what is claimed as new and desired to be secured by Letters Patent is y I. In a-terra cotta firing system, a kiln having a continuous side wall, and an entirely closed. bottom a relatively low bag wall extending around the inside of said kiln to form a continuous space between said side wall and bag wall a continuous bottom between said side wall and bag-wall substantially in the plane ofthe bottom of said kiln and a plurality of openings extending thru said side wall,

and communicating with said continuous space.

2; Ina terra cotta firing system a kiln'hav ing a continuous side wall, a relatively low bag wall extending around the inside of said kiln to form a continuous space between said side wall and bag wall, a plurality of openings through said side wall and communicating with-said continuous space, an entirely substantially horizontal closed bottom for said kiln extending to the side wall, a stack In testimony whereof, I. hereunto afiix my signature. r

' ALBERT H. SHEFFIELD.

l8, and into the kiln, as the kiln rises in temperature, additional burners may be lit and turned low until about the sixth hour, when the full number of burners maybe lit and, if the, bottom of the kiln is lagging behind, the dampers may be. closed a small amount, which will put pressure on the top of the kiln to force the to Experience 

